Fairfield Bay is located at 35°35'38" North, 92°16'40" West (35.593889, -92.277778).

According to the United States Census Bureau, the city has a total area of 15.19 mi2 (39.34 km2). 15.18 mi2 (39.32 km2) of it is land and 0.01 mi2 (0.02 km2) of it is covered by water. The total area is 0.05% water.

Fairfield Bay is located in the Central Standard Time (CST) timezone, GMT-06:00. It observes Daylight Saving Time (DST).